Answer:
5. 314.16 feet squared
6. 615.75 inches squared
7. 254.47 kilometers squared
8. 380.13 yards squared
Explanation:
A=πr^2
For 5 and 6 plug in the numbers and multiply. For 7 and 8, they give you the diameter, to find the radius, simply divide the number by 2, then plug the number into the formula.
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